适合文昌油田中高含水筛管井的复合酸液体系

A Compound Acid for Medium to High Water-cut Screen Pipe Completed Wells in Wenchang Oilfield

南海西部文昌油田群部分油井已进入中高含水期,储层具有胶结疏松、非均质性强等特点,多采用悬挂筛管完井,酸化时很难实现均匀布酸,往往出现增液不增油的现象。针对储层特点及完井方式,研发出了WZX-02自转向酸+WHS-05缓速酸的复合酸液体系,该体系能有效抑制酸液进入高渗层,避免酸化后含水大幅上升。该体系在文昌M油田D井进行了先导性试验,酸化前产液量为68 m^3/d,产油量为32 m^3/d,含水53%,酸化后产液量为207 m^3/d,产油量为117 m^3/d,含水43%,增产效果显著,可为类似中高含水筛管井酸化提供借鉴。

Some oil wells in the Wenchang Oilfield(located in the west o f South China Sea),which were completed with screen pipe,are now having high water-cut.In acidizing operations,acids are difficult to be distributed evenly,thus the production of fluid is increased,while the production o f oil remains low.Based on the characteristics of the reservoir rocks and the well completion method usedj a compound acids,formulated with a self-diverting acid WZX-02 and a retarding acid WHS-05,was developed to deal with the said problems.The compound acids are able to control themselves from entering into formations of high permeability,thereby avoiding water-cut increase after acidizing operations.The compoimd acids have been pilot tested on the Well D in Block M in Wenchang oilfield.Prior to acidizing,the well had liquid production of 68 m3/d,oil production of 32 m3/d,and water-cut of 53%.After acidizing,the liquid production increased to 207 m3/d,oil production to 117 m3/d,and water-cut reduced to 43%,demonstrating that the compound acids had remarkable ability in oil production enhancement,and can be used in acidizing screen pipe completed wells with high water-cut.